Net Zero homes are a reality.2011 Solar Decathlon Washington DC.

Every two years the US Department of Energy (DOE) solicits proposals from colleges all around the world to compete in their Solar Decathlon. The goal of the competition is to build affordable homes that are livably net zero. The selected teams receive initial monies from the DOE to get started, but must raise the rest to further their project. Each team must design and build a 1000 square foot home that uses as much energy (electricity, space heating,water heating, cooling) as it produces.

The teams build and design the homes at their respective campuses, then they have to break them down and transport them to Washington DC for a 10 day, 10- category competition from Sept. 23-Oct.2nd. The teams are judged on Architecture, Communications, Market Appeal, Engineering, Affordability, Comfort Zone, Hot Water, Appliances, Home entertainment and Energy Balance. This year's event had an estimated 150,000 visitors over the course of the competition from Sept. 23-Oct.2, 2011.

To score points in the competition homes must make the most of the energy they generate. All homes incorporated solar electric modules and or solar thermal to harvest the energy from the sun. Teams that generated as much power as they used scored 100 points in the Energy Balance category. Many teams used passive solar architecture as well as active solar collectors.

All the homes at the Solar Decathlon really captured the essence of their state, city or country. That was very evident with the hip X-Box styled California beach pod home to the New York City modular home that was designed to be transported in an elevator and constructed on top of an existing structure. The New Zealand home may have been in Washington DC, but it smelled and felt like I was in New Zealand.

The homes must also be affordable, be livable and be functional. Teams had to be careful not to go too far in their design, but enough to show effective and functional use of engineering, architecture and lighting design. Most homes utilized quite a bit of natural daylighting to help alleviate the need for electricity to power lights. During the course of the competition each team must wash a load of laundry, host a dinner party, run appliances and cook several meals. Panels of judges visit the homes to see how each home is finished, how it functions, how it is constructed and how each design actually works during normal day to day routines.

Lookout now cause I'm using technology. Almost every team had a mobile app to load on to your smart phone with the ability to manage the homes lighting, adjust thermostat settings and loads.

Here is the breakdown of our favorites:

Purdue University: We really liked the Purdue “INHome” house, not because we helped as a sponsor, but because it felt midwestern, understated and pragmatic. It didn't finish high on architecture, as it would not have looked out of place in your neighborhood, but it did everything thing else very well. The 8.64 KW solar array aesthetically blended into the roofline. Their biowall is a natural vertical wall that relies on plants to provide an air filtration system. The “INHome” had very sorted smart phone controls that showed energy consumption, enabled you to manage the thermostat, door locks, lighting. It had a very nice passive solar design with high ceilings and windows to let moving air thru the home. The home felt comfortable with the natural air movement thru the home and overall it was relaxed very familiar. The INHome incorporated Structural Insulated building Panels (SIPS) to increase insulation levels. The home scored well in energy balance and affordability. Purdue took home second place overall, which is amazing considering it was their first attempt.

Appalachian State: Their “Solar Homestead” achieved an interesting incorporation of green build techniques with more conventional construction. Their design utilized a living green roof which manages runoff and creates additional insulation. The Homestead featured modular “Flex-OM” pods which are energy independent, conditioned living spaces. There were solar thermal collectors integrated into the kitchen and bath skylight.The Solar Homestead had a large outdoor living porch that provided a comfortable outdoor space for gatherings. There was also an outdoor living module for a studio or office that was finished bi-facial solar canopy (they collect solar energy from both sides of the module) a living roof as well as poplar bark siding. The outbuilding is built on a 8' x 16' trailer, so the module can be transported by a pick up, van or suv. The finishing touch to me, was the 8.2 KW bifacial solar modules that was architecturally integrated as the canopy for their great porch. Appalachian State finished in 12th but won the people's choice award.

Team China: Their “Y-container” entry didn't finish high with the judges, (15th) but we really liked what they did. Team China utilized recycled shipping containers in a “Y” shape to great effect. The home felt large and spacious. By using disposed shipping containers they got very high marks in my book for creativity, recycling and affordability. The design, I'm sure was also helpful in shipping the home overseas and assembling quickly. Their lighting design incorporated skylights that also had led lighting integrated as well for night time The bedroom had sliding walls to create a private one or two bedroom living space.

Middlebury College:Their “Self-Reliance” entry will not wow you with architecture, but won us over with some really interesting features. The New England style farmhouse used thick walls and triple paned windows to ward off the cold New England winters. We really liked the green wall in the kitchen so you can grow fresh produce year-round. The kitchen space was also open and inviting. The house had natural hardwood flooring and lots of windows for plenty of natural daylighting. An air-to-air heat exchanger that circulates air through a network of aluminum ducts and feeds the green wall with condensed moisture. The furniture was hand made by the students and featured a fold up style murphy bed to utilize living space. To me, it just felt very livable. Middlebury College finished 4th.University of Maryland: Their “WaterShed” entry probably incorporated the most technologies in their their home. It had a living roof, a constructed wetland, vertically mounted solar thermal, not to mention solar PV, a liquid desiccant waterfall to dehumidify the home and a grey water collection system to feed their vertical garden. They incorporated all of these very well and didn't detract from the overall aesthetic of the home. The home was open, airy and Maryland seemed to really relish the opportunity to show off these technologies. Their home was one of the most expensive, but they won the Architecture award and along the way ended up winning the entire competition.

The experience the teams got was phenomenal. The Purdue students are poised to take what they have learned to the streets. I think we will start to see a group of hungry young architects, designers and builders incorporating net zero ideas and making them a reality.

Each team's design information, plans, products utilized can be accessed thru their respective team websites listed below. Investigate these amazing cutting edge designs and utilize their construction manuals as a potential resource for new home or retro-fit construction project. One of the DOE's goal's is to raise public awareness and further the acceptance of renewable energy technologies.